Way cool! It actually looks better than cups, too, if you want the water to go IN you AND you don't have to drink all your water at once. I would love to see this at more races.

As for the water in/on you, maybe if you carried two of them, or carried a single regular dixie cup that you could use to pour water on yourself, or as you said filled it once, poured it on, filled it again, carried it for drinking? I'm big on the water on myself during races, so I'll be curious to see how that works out. Actually, maybe if you filled/carried two of them, you could pour water on yourself periodically, which would be super awesome.

I have heard that a lot of races recycle the paper cups now, but it still seems wasteful.